Revert "Rename 3p1_fixed/simplex.lisp to 3p1_fixed_simplices/simplex.lisp"

This reverts commit 501cfd2c3730c37814fe4c3af2000cad8f1a3761.

	2p1-fixed-boundaries/13h-29d-7m-2013-dewitt.phasemap
	2p1-fixed-boundaries/IB0500_FB0500.file_list
	2p1-fixed-boundaries/S2-OPEN-T040-V0100K-autocorrelation.txt
	2p1-fixed-boundaries/T028-IB0900-FB0900-2-400-10-diffusion.filelist
	2p1-fixed-boundaries/T028_minimal_boundary.file_list
	2p1-fixed-boundaries/T035_post_thermalization.lisp
	2p1-fixed-boundaries/c_data_analysis_code/stsDiffusion2p1SI
	2p1-fixed-boundaries/c_data_analysis_code/stsDiffusion2p1SInew
	2p1-fixed-boundaries/fb0100_check_data.lisp
	2p1-fixed-boundaries/high_throughput_scripts/make_post_thermalization_script_dewitt.sh
	2p1-fixed-boundaries/high_throughput_scripts/make_post_thermalization_scripts_janus.sh
	2p1-fixed-boundaries/nohup.out
	2p1-fixed-boundaries/start_therm.sh
	2p1-fixed-boundaries/stsDiffusion2p1SI
	2p1-fixed-boundaries/stsDiffusion2p1SInew
	2p1-fixed-boundaries/test_simplices.lisp
	2p1-fixed-boundaries/tetra.txt